<template>
    <view class="u-search" @tap="clickHandler" :style="[{
        margin: margin,
    }, $u.addStyle(customStyle)]">
        <view class="u-search__content" :style="{
            backgroundColor: bgColor,
            borderRadius: shape == 'round' ? '100px' : '4px',
            borderColor: borderColor,
        }">
            <template v-if="$slots.label || label !== null">
                <slot name="label">
                    <text class="u-search__content__label">{{ label }}</text>
                </slot>
            </template>
            <view class="u-search__content__icon">
                <u-icon @tap="clickIcon" :size="searchIconSize" :name="searchIcon"
                    :color="searchIconColor ? searchIconColor : color"></u-icon>
            </view>
            <input confirm-type="search" @blur="blur" :value="keyword" @confirm="search" @input="inputChange"
                :disabled="disabled" @focus="getFocus" :focus="focus" :maxlength="maxlength"
                placeholder-class="u-search__content__input--placeholder" :placeholder="placeholder"
                :placeholder-style="`color: ${placeholderColor}`" class="u-search__content__input" type="text" :style="[{
                    textAlign: inputAlign,
                    color: color,
                    backgroundColor: bgColor,
                    height: $u.addUnit(height)
                }, inputStyle]" />
            <view class="u-search__content__icon u-search__content__close" v-if="keyword && clearabled && focused"
                @tap="clear">
                <u-icon name="close" size="11" color="#ffffff" customStyle="line-height: 12px"></u-icon>
            </view>
        </view>
        <text :style="[actionStyle]" class="u-search__action"
            :class="[(showActionBtn || show) && 'u-search__action--active']" @tap.stop.prevent="custom">{{ actionText
            }}</text>
    </view>
</template>

<script>
import props from './props.js';
import mpMixin from '../../libs/mixin/mpMixin.js';
import mixin from '../../libs/mixin/mixin.js';

/**
 * search 搜索框
 * @description 搜索组件，集成了常见搜索框所需功能，用户可以一键引入，开箱即用。
 * @tutorial https://ijry.github.io/uview-plus/components/search.html
 * @property {String}			shape				搜索框形状，round-圆形，square-方形（默认 'round' ）
 * @property {String}			bgColor				搜索框背景颜色（默认 '#f2f2f2' ）
 * @property {String}			placeholder			占位文字内容（默认 '请输入关键字' ）
 * @property {Boolean}			clearabled			是否启用清除控件（默认 true ）
 * @property {Boolean}			focus				是否自动获得焦点（默认 false ）
 * @property {Boolean}			showAction			是否显示右侧控件（默认 true ）
 * @property {Object}			actionStyle			右侧控件的样式，对象形式
 * @property {String}			actionText			右侧控件文字（默认 '搜索' ）
 * @property {String}			inputAlign			输入框内容水平对齐方式 （默认 'left' ）
 * @property {Object}			inputStyle			自定义输入框样式，对象形式
 * @property {Boolean}			disabled			是否启用输入框（默认 false ）
 * @property {String}			borderColor			边框颜色，配置了颜色，才会有边框 (默认 'transparent' )
 * @property {String}			searchIconColor		搜索图标的颜色，默认同输入框字体颜色 (默认 '#909399' )
 * @property {Number | String}	searchIconSize 搜索图标的字体，默认22
 * @property {String}			color				输入框字体颜色（默认 '#606266' ）
 * @property {String}			placeholderColor	placeholder的颜色（默认 '#909399' ）
 * @property {String}			searchIcon			输入框左边的图标，可以为uView图标名称或图片路径  (默认 'search' )
 * @property {String}			margin				组件与其他上下左右元素之间的距离，带单位的字符串形式，如"30px"   (默认 '0' )
 * @property {Boolean} 			animation			是否开启动画，见上方说明（默认 false ）
 * @property {String}			value				输入框初始值
 * @property {String | Number}	maxlength			输入框最大能输入的长度，-1为不限制长度  (默认 '-1' )
 * @property {String | Number}	height				输入框高度，单位px（默认 64 ）
 * @property {String | Number}	label				搜索框左边显示内容
 * @property {Object}			customStyle			定义需要用到的外部样式
 *
 * @event {Function} change 输入框内容发生变化时触发
 * @event {Function} search 用户确定搜索时触发，用户按回车键，或者手机键盘右下角的"搜索"键时触发
 * @event {Function} custom 用户点击右侧控件时触发
 * @event {Function} clear 用户点击清除按钮时触发
 * @example <u-search placeholder="日照香炉生紫烟" v-model="keyword"></u-search>
 */
export default {
    name: "u-search",
    mixins: [mpMixin, mixin, props],
    data() {
        return {
            keyword: '',
            showClear: false, // 是否显示右边的清除图标
            show: false,
            // 标记input当前状态是否处于聚焦中，如果是，才会显示右侧的清除控件
            focused: this.focus
            // 绑定输入框的值
            // inputValue: this.value
        };
    },
    watch: {
        keyword(nVal) {
            // 双向绑定值，让v-model绑定的值双向变化
            // #ifdef VUE3
            this.$emit("update:modelValue", nVal);
            // #endif
            // #ifdef VUE2
            this.$emit('input', nVal);
            // #endif
            // 触发change事件，事件效果和v-model双向绑定的效果一样，让用户多一个选择
            this.$emit('change', nVal);
        },
        // #ifdef VUE3
        modelValue: {
            immediate: true,
            handler(nVal) {
                this.keyword = nVal;
            }
        },
        // #endif
        // #ifdef VUE2
        value: {
            immediate: true,
            handler(nVal) {
                this.keyword = nVal;
            }
        },
        // #endif
    },
    computed: {
        showActionBtn() {
            return !this.animation && this.showAction
        }
    },
    emits: ['clear', 'search', 'custom', 'focus', 'blur', 'click', 'clickIcon', 'update:modelValue', 'change'],
    methods: {
        // 目前HX2.6.9 v-model双向绑定无效，故监听input事件获取输入框内容的变化
        inputChange(e) {
            this.keyword = e.detail.value;
        },
        // 清空输入
        // 也可以作为用户通过this.$refs形式调用清空输入框内容
        clear() {
            this.keyword = '';
            // 延后发出事件，避免在父组件监听clear事件时，value为更新前的值(不为空)
            this.$nextTick(() => {
                this.$emit('clear');
            })
        },
        // 确定搜索
        search(e) {
            this.$emit('search', e.detail.value);
            try {
                // 收起键盘
                uni.hideKeyboard();
            } catch (e) { }
        },
        // 点击右边自定义按钮的事件
        custom() {
            this.$emit('custom', this.keyword);
            try {
                // 收起键盘
                uni.hideKeyboard();
            } catch (e) { }
        },
        // 获取焦点
        getFocus() {
            this.focused = true;
            // 开启右侧搜索按钮展开的动画效果
            if (this.animation && this.showAction) this.show = true;
            this.$emit('focus', this.keyword);
        },
        // 失去焦点
        blur() {
            // 最开始使用的是监听图标@touchstart事件，自从hx2.8.4后，此方法在微信小程序出错
            // 这里改为监听点击事件，手点击清除图标时，同时也发生了@blur事件，导致图标消失而无法点击，这里做一个延时
            setTimeout(() => {
                this.focused = false;
            }, 100)
            this.show = false;
            this.$emit('blur', this.keyword);
        },
        // 点击搜索框，只有disabled=true时才发出事件，因为禁止了输入，意味着是想跳转真正的搜索页
        clickHandler() {
            if (this.disabled) this.$emit('click');
        },
        // 点击左边图标
        clickIcon(e) {
            this.$emit('clickIcon', this.keyword);
            try {
                // 收起键盘
                uni.hideKeyboard();
            } catch (e) { }
        }
    }
}
</script>

<style lang="scss" scoped>
@import "../../libs/css/components.scss";
$u-search-content-padding: 0 10px !default;
$u-search-label-color: $u-main-color !default;
$u-search-label-font-size: 14px !default;
$u-search-label-margin: 0 4px !default;
$u-search-close-size: 20px !default;
$u-search-close-radius: 100px !default;
$u-search-close-bgColor: #C6C7CB !default;
$u-search-close-transform: scale(0.82) !default;
$u-search-input-font-size: 14px !default;
$u-search-input-margin: 0 5px !default;
$u-search-input-color: $u-main-color !default;
$u-search-input-placeholder-color: $u-tips-color !default;
$u-search-action-font-size: 14px !default;
$u-search-action-color: $u-main-color !default;
$u-search-action-width: 0 !default;
$u-search-action-active-width: 40px !default;
$u-search-action-margin-left: 5px !default;

/* #ifdef H5 */
// iOS15在H5下，hx的某些版本，input type=search时，会多了一个搜索图标，进行移除
[type="search"]::-webkit-search-decoration {
    display: none;
}

/* #endif */

.u-search {
    @include flex(row);
    align-items: center;
    flex: 1;

    &__content {
        @include flex;
        align-items: center;
        padding: $u-search-content-padding;
        flex: 1;
        justify-content: space-between;
        border-width: 1px;
        border-color: transparent;
        border-style: solid;
        overflow: hidden;

        &__icon {
            @include flex;
            align-items: center;
        }

        &__label {
            color: $u-search-label-color;
            font-size: $u-search-label-font-size;
            margin: $u-search-label-margin;
        }

        &__close {
            width: $u-search-close-size;
            height: $u-search-close-size;
            border-top-left-radius: $u-search-close-radius;
            border-top-right-radius: $u-search-close-radius;
            border-bottom-left-radius: $u-search-close-radius;
            border-bottom-right-radius: $u-search-close-radius;
            background-color: $u-search-close-bgColor;
            @include flex(row);
            align-items: center;
            justify-content: center;
            transform: $u-search-close-transform;
        }

        &__input {
            flex: 1;
            font-size: $u-search-input-font-size;
            line-height: 1;
            margin: $u-search-input-margin;
            color: $u-search-input-color;

            &--placeholder {
                color: $u-search-input-placeholder-color;
            }
        }
    }

    &__action {
        font-size: $u-search-action-font-size;
        color: $u-search-action-color;
        width: $u-search-action-width;
        overflow: hidden;
        transition-property: width;
        transition-duration: 0.3s;
        /* #ifndef APP-NVUE */
        white-space: nowrap;
        /* #endif */
        text-align: center;

        &--active {
            width: $u-search-action-active-width;
            margin-left: $u-search-action-margin-left;
        }
    }
}
</style>
